Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH] sched/cpufreq: Align trace event behavior of fast switching | Date | Wed, 28 Aug 2019 11:44:30 +0200 |
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On Monday, August 26, 2019 11:40:58 AM CEST Peter Zijlstra wrote: > On Mon, Aug 26, 2019 at 11:10:52AM +0200, Rafael J. Wysocki wrote: > > On Wednesday, August 7, 2019 5:33:40 PM CEST Douglas RAILLARD wrote: > > > Fast switching path only emits an event for the CPU of interest, whereas the > > > regular path emits an event for all the CPUs that had their frequency changed, > > > i.e. all the CPUs sharing the same policy. > > > > > > With the current behavior, looking at cpu_frequency event for a given CPU that > > > is using the fast switching path will not give the correct frequency signal. > > > > > > Signed-off-by: Douglas RAILLARD <douglas.raillard@arm.com> > > > --- > > > kernel/sched/cpufreq_schedutil.c | 7 ++++++- > > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > > > diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c > > > index 1f82ab108bab..975ccc3de807 100644 > > > --- a/kernel/sched/cpufreq_schedutil.c > > > +++ b/kernel/sched/cpufreq_schedutil.c > > > @@ -153,6 +153,7 @@ static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time, > > > unsigned int next_freq) > > > { > > > struct cpufreq_policy *policy = sg_policy->policy; > > > + int cpu; > > > > > > if (!sugov_update_next_freq(sg_policy, time, next_freq)) > > > return; > > > @@ -162,7 +163,11 @@ static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time, > > > return; > > > > > > policy->cur = next_freq; > > > - trace_cpu_frequency(next_freq, smp_processor_id()); > > > + > > > + if (trace_cpu_frequency_enabled()) { > > > + for_each_cpu(cpu, policy->cpus) > > > + trace_cpu_frequency(next_freq, cpu); > > > + } > > > } > > > > > > static void sugov_deferred_update(struct sugov_policy *sg_policy, u64 time, > > > > > > > Peter, any comments here? > > I was thinking this would be a static map and dealing with it would be > something trivially done in post (or manually while reading), but sure, > whatever: > > Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> >
Thanks, queuing up this one for 5.4.
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